torsdag 16 november 2017

Super Express - how super?

The new Hitachi bi-mode trains are now coming into service; after the embarrassing maiden trip, it is possible to make a more balanced judgement. It will be a while before I get an opportunity to travel in them, but the verdict seems to be that the underfloor engines are not too bothersome and the main complaints are about the hardness of the  seats. The air conditioning problem on the inaugural run was due to the failure of the pump which removes the condensed water, but one wonders why the system was designed to need one, when previous air conditioning systems relied on gravity to drain away the condensate. What became of the principle of keeping things simple?

Ian Walmsley, writing in Modern Railways, said that the Great Western ones so far running are all right as commuter trains, but not much better than that. The big question mark concerns performance. The engines were supposed to have been de-rated to improve reliability, but this will have a detrimental effect on timekeeping, especially now that so much of the electrification is uncompleted and likely to remain so for a long time to come. There are also unsolved issues such as the bridge over the main line at Steventon; until it is resolved, there will be a break in the electrification. Given the problems with changeover from diesel to electric on the first journey, having to carry out the operation is going to create a long-term risk to reliability. This saga is going to run for a few years yet.

In 1985 I was the co-author of an article that was published in the Railway Magazine, written slightly tongue-in-cheek, suggesting that the Great Western Main Line should be electrified on the third rail system. Perhaps the idea was not so daft.

Tunnel of steel not needed after all


It now turns out that the Great Western Main Line's "Tunnel of Steel" was not necessary after all. It seems, as Roger Ford explains in "Informed Sources", that there were design errors which went unnoticed.

There have indeed been problems with overhead electrification on the East Coast Main line, which was carried out to super-economical standards, but the West Coast route, electrified in the 1970s, has performed reliably even though it passes through some of the most exposed uplands in the country; in comparison, it looks like gossamer.

lördag 21 oktober 2017

IEP problems - give them a break

The very public failures of the Hitachi IEP on its first run in public service have been the subject of much criticism in the press. I am no fan of this project but the criticism is unfair at this stage. It takes at least a couple of years in public service to get a new design of train working reliably.

British Railways Mark 1 stock is often held up as an example of robust simplicity, but its introduction was plagued with problems. The ride quality of the trains deteriorated rapidly due to the design of the BR1 type double bolster bogie. This led to the setting up of a research programme which eventually resulted in the B4 bogie, but that took almost a decade. In the meantime, the Commonwealth bogie with cast steel frame was adopted as an interim replacement; the ride quality was much improved but it was a heavy piece of equipment.

Ride quality became even more of an issue when the mark 1 stock was adapted as an electric multiple unit design for service on the newly electrified Kent Coast lines in 1959. The standard BR bogie was modified due to the reduced clearances on the route. So bad was the ride quality that the trains became known as the "Rock and Roll Trains". The ride over the motor bogies was even worse.

That was not all. The double glazing seals did not work and the spaces between the panes filled up with water, so the inner panes were removed, with double glazing not being reinstated until the trains were given a mid-life refurbishment in 1981.

Mark 1 stock also suffered badly from corrosion from the inside out, especially around the windows. The window problem was eventually resolved by placing the windows in aluminium frames, but corrosion remains an issue for the preservation movement which relies on these vehicles.

Similar reliability issues affected the locomotives. The flagship express steam locomotive Duke of Gloucester was a notoriously poor performer and was quickly dispatched to the scrapyard. Years later, it was rescued and the original design team brought together with a view to discovering the cause of the problems. These turned out to be a combination of inaccurate construction and bad design decisions arising from office politics. Once most of the faults had been corrected, the performance of the machine was transformed, making it possibly the best of the British express designs. Before that there had been the issues with the Bulleid Pacfics, which were troublesome until they received their major rebuild in the mid-1950s, following a serious accident.

The issues continued with subsequent generations of stock.  Rust affected the earlier Mark 2 stock and the suburban versions of Mark 3; the class 455 stock need a major repairs as the floors dissolved into flakes of rust. Air conditioning was unreliable until about ten years ago. Electrostars were another class which did not settle down for almost five years after they first came into service.

It is possible to build new trains which will run reliably, but they have to be technically conservative. The new locomotive hauled fleet for Northern should go into service without problems, since they will be pulled by locomotives which have been in use for several years and hauled carriages are a simpler affair altogether. But given the complexity of the IEP, and based on historical experience, it is too soon to start criticising. The design is indeed complicated, unnecessarily so, and costs about double what it ought to have done. But those decisions were made by the civil servants and the Department for Transport. Hitachi and its engineers should not be made to take the blame.

onsdag 11 oktober 2017

New Thameslink nasties





The new class 700 Siemens trains are even worse than the class 319 stock which it replaces.
  • There is nowhere to put a cup of coffee apart from balanced on one's lap. Had the designers never heard of "food to go"? Do they even travel in trains?
  • The uncomfortable seats have no spacers in between the pairs so if there is one large person in the window seat, his or her neighbour will be half-way off the seat by the gangway.
  • The skirting level duct cuts into the space to put one's feet so that one is forced to sit twisted round.
  •  The lighting is dim - there is only a strip in the centre of the ceiling.
  • What is the reason for the curved shape of the windows?
Horrible trains, and you can be sitting or standing in them for well over an hour as they are used on the line between Brighton and Bedford.

onsdag 16 augusti 2017

UK electrification schemes cancelled #2

The new GW electrification is noteworthy for the chunkiness of the overhead structures, which are heavier than the notably solid gantries installed for the 1500kV Great Eastern electrification which was installed in 1949. One of the reasons for the adoption of 25kV electrification was that the smaller current flows made it possible to use thinner and lighter contact wires, and consequently lighter and cheaper structures. The Great Western's tunnel of steel must come at a commensurately heavy price, which has helped to push further electrification schemes into the realm of the unaffordable.

The overhead structures for the 15kV system used in Switzerland, Germany and Sweden are like gossamer in comparison. What has happened to let loose this orgy of over engineering?

UK electrification schemes cancelled #1

I have tried without success to discover the underlying reason why major UK electrification schemes have been cancelled.

As I understand it, electrification costs have increased due to new regulations which require more generous clearances in relation to 25kV overhead wires and on-train equipment. What I have not been able to find out is where these new regulations have come from. As far as I can mak out, their immediate source is  the Office of Rail Regulation (ORR), which has adopted Electricity at Work Regulations. But when and where have these come from? Has there been an input from the EU's regulatory bodies?

If they are an EU requirement, was there an application for derogation having regard to the special circumstances in the UK? If not, why not?

To whom, if anyone, is the ORR answerable?

tisdag 10 januari 2017

Support pulled from D-train

The D-train is a project to recycle the London Underground's District Line D78 stock, introduced in 1978. It was heavily refurbished between 2000 and 2003 with new bogies and other equipment. It is basically in sound condition and good until at least 2025, but it was decided to replace it with the S-stock to provide London Underground surface lines with, for the first time, a uniform fleet.

This will in due course almost certainly prove to have been a bad strategy for London. Railway rolling stock tends to suffer from some weaknesses which show up almost immediately, and others which show up after a decade or two, in both cases affecting the entire fleet. The thirty Bulleid-designed Merchant Navy class all had to be taken out of service and eventually rebuilt, following an incident in 1953 which revealed a fundamental failure with the design. A similar thing happened with the thirty GWR King class locomotives after it had been in service for almost thirty years. It would be good luck if the entire fleet of S-stock is not eventually affected by some defect which means that it will all have to be taken out of service for remedial action.

But to return to the D78 stock. Adrian Shooter saw the opportunity to recycle this stock for secondary services on the national system. In principle that was a shrewd move, though easier said than done, because the trains are electrically powered and the intention is to operate them on lines which are not electrified. The chosen approach was to install underfloor engines to power generators to drive the trains' existing electric motors.

This might have sounded like an economical solution, but fitting generators under the floor of a train can be tricky; the weight of the equipment is one difficulty and the lack of space another.

And so it has proved. The initial use of the trains, now designated class 230, was intended to be between Nuneaton and Coventry. However, an engine caught fire on the trial run and the backers have pulled out of the project. That seems like a precipitate decision, but the project, it is claimed, has now been delayed to the point that it could not meet the timetable set for development.

One has to wonder about the thinking that lay behind the notion. Putting the generator in a separate and reasonably spacious compartment would have been easier and less likely to run into trouble. Using the carriages as locomotive-powered push-pull sets would have been even less risky, and more flexible too, especially if the locomotives used in the trial had been of a well-established type such as the class 20 or 37, of which a number are still serviceable.

Then there is this, specifically designed for secondary routes, within the constraints of the contemporary railway environment. It is nearly eight years since the developer, DLM-AG of Winterthur, came up with the proposal. The firm has so far failed to find sufficient interest for the minimum build of twenty units, costing around £30 million in total, which would be necessary to achieve a favourable price, around 30% of that of a comparable diesel locomotive.